Identification of a new HLA-B null allele,B*1817 N,in a family

We describe a new HLA-B null allele found in a daughter and her mother. This null allele was due to a mutation at position 41 of exon 1 which resulted in a premature stop codon. This new null allele was officially named HLA-B*1817N*.     

HLA-B*0749N: the first HLA-B*07 null allele

In the present article, we report the identification of the first HLA-B*07 null allele found in a Polish patient awaiting a kidney allograft. A discrepant result obtained between serological typing (HLA-B "blank") and high-resolution molecular typing using PCR-SSP method (HLA-B*070201 allele) suggested the presence of a null allele. Genomic DNA sequencing of the HLA-B*07 allele revealed a single nucleotide substitution at the 3' end of the exon 4 leading to a premature stop codon.     

A novel HLA-B*51 allele, HLA-B*5149

Discovery of the novel HLA-B*5149 allele in a North American Caucasian individual is described. It differs from B*510101 by one nucleotide within the coding sequence of exons 1-6. A substitution at nucleotide position 488 in exon 3 changes alanine to glycine in amino acid position 139.     

A novel HLA-B null allele (B*4022N) generated by a nonsense codon in the alpha1 domain

We describe in this work a novel HLA-B null allele designated B*4022N. This new variant was found in a Caucasian individual who was serologically typed for one HLA-B allele as a B-blank, Bw-blank. Retrospective DNA typing by polymerase chain reaction using sequence-specific primers (PCR-SSP) has established the correspondence of this blank allele with the classical HLA-B*4001 allele. Nucleotide sequence analysis of exon 2 and 3 has revealed the presence of two adjacent point mutations at position 170 and 171 of exon 2 (GG to TT). While the first difference is silent, the second leads to the creation of a nonsense codon at position 58 of the alpha1 domain, providing the most likely mechanism underlying the observed null phenotype.     

新等位基因HLA-B*9526的确认和序列分析

目的 鉴定中国人群中人类白细胞抗原(human leukocyte antigen,HLA)新等位基因HLA-B*9526,并进行核苷酸序列分析.方法 使用序列特异性寡核苷酸PCR技术进行HLA基因分型,发现1个反应格局异常的等位基因,应用分子克隆和DNA双向测序技术测定新等位基因的核苷酸序列,并与已知等位基因进行序列比对分析.结果 检出反应格局异常的DNA样本,经过克隆测序得到两个等位基因,分型结果一个为B*5403,另一个的核苷酸序列与已知的HLA等位基因均不同,该基因序列与同源性最高的HLA-B*1507基因序列相比在第3外显子区域中425位碱基发生A→G突变,导致142位编码氨基酸由酪氨酸变成半胱氨酸.结论 一个新的HLA-B等位基因被确认,并被世界卫生组织HLA因子命名委员会正式命名为HLA-B*9526.     

Characterization of the novel allele HLA-B*4075

A novel human leukocyte antigen (HLA)-B allele, B*4075, is the close matching allele B*40060101 by one nucleotide substitution in exon 2, at position 272 C→G, which leads to a amino acid change at codon 67 from Ser to Cys (S67C).     

A novel HLA-B*40 allele, HLA-B*4083, identified in a Korean individual

HLA-B*4083 differs from the closest aligned sequence HLA-B*400601 by three nucleotide substitutions at codons 31 (ACG →ACC), 32 (CTG →CAG), and 41 (ACG → GCG), resulting in two amino acid changes at residues 32 (Leu to Gln) and 41 (Thr to Ala).     

Full length sequence of a novel HLA-B*132202 allele

Full length sequences of this novel HLA-B*132202 allele are identical to those of HLA-B*132201 allele, except for a synonymous amino acid substitution from ACG to ACC at codon 138 in exon 3.     

Identification of a novel HLA-B*56 allele, B*5618 and an extension of B*2736 by sequence-based typing

We report the identification of a novel human leukocyte antigen (HLA)-B*56 allele, B*5618 and an extension of B*2736 that were found during routine high-resolution sequence-based typing in Chinese Han individual. The B*5618 allele has 4nt changes from B*5610 in exon 3, The B*2736 allele has 10nt changes from B*270401 in exons 3-4.     

An HLB-B null allele (B*0808N) caused by a nucleotide deletion in exon 3, found in the family of a bone marrow transplant recipient

We have identified a variant HLA-B allele, B*0808N, segregating through two generations of healthy individuals, whilst HLA typing the family of a bone marrow patient. Serological typing identified a disparity between the father (A1, A3 B7 DR7) and the brother (A1, A2 B56 DR1, DR7) of the patient. Low/medium resolution polymerase chain reaction using sequence-specific primers (PCR-SSP) revealed a B*08 allele undetectable by serological methods. High resolution DNA typing by polymerase chain reaction-sequencing based typing (PCR-SBT), revealed a nucleotide deletion at position 131 (C) in exon 3, the only difference between the new allele and B*0801. The deletion results in a frame shift in the protein coding sequence, introducing a premature termination codon (TGA) in exon 4. Although a B*08 allele is present in these individuals, the deletion prevents correct expression of the antigen on the cell surface.     

A new HLA-A*02 null allele, HLA-A*9213N

A novel HLA-A*02 null allele, differing from HLA-A*02010101 at codon 60 (TGG tryptophan-->TAG stop), is described.     

Identification of a novel HLA-B allele HLA-B*9526 in a Chinese donor

A novel human leukocyte antigen-B (HLA-B) allele, B*9526, was identified. The B*9526 allele has one nucleotide change from the closest matching allele B*1507 resulting in an amino acid change from Y(TAC) to C(TGC) at codon 142.     

Identification of a novel HLA-B*40 allele, HLA-B*4071, by sequence-based typing

HLA-B*4071 allele shows six nucleotides difference from B*4005 allele in exon 3 at nucleotides 419A>T, 420C>A, 463C>A, 477C>G, 486G>C and 527A>T, resulting in three amino acid changes Tyr116Leu, Arg131Ser and Glu152Val.     

DRB1*1613N: a novel DRB1 allele with a premature termination codon

DRB1 null alleles are extremely rare and always sporadic, suggesting their biological selective disadvantage.     

A frame shift due to a two-nucleotide deletion results in an HLA-B null allele, B*9549N

This report describes the identification of a new human leukocyte antigen (HLA) class I null allele, B*9549N, resulting from a premature stop codon in exon 3.     

A novel HLA-B*46 allele, B*4609, identified by sequence-based typing in a Chinese donor

A novel human leukocyte antigen-B allele, B*4609, has been identified. The B*4609 allele has one nucleotide change from the closest matching allele B*460101 resulting in an amino acid change from E (GAG) to V (GTG) at codon 176.     

A novel HLA-B*15 allele, B*9524, identified by sequence-based tying in the Chinese population

We report here the identification of a novel human leukocyte antigen (HLA)-B*9524 allele that was detected by polymerase chain reaction sequence-based typing.